Tack button



y 1941- F. G. PURINTON ET AL 2,243,017

TACK BUTTON Filed Jan. 3, 1939 3mm: IYo -nesZ' G. Purim-Eon, "MZiz'ZZz'am A Zwiehel, m:

ter,

Patented May 20, 1941 HTD TACK BUTTGN Application January 3, 1939, Serial No. 249,138

(Cl. 2 l9) lil Claims.

Our invention relates to new and useful improvements in buttons, and more particularly to a tack button.

As is well known to those skilled in the art, tack buttons are those which are used on overalls, work clothes, and the like and are permanently attached by driving a fastener, such as a tack or staple, through the goods and up into the button head, where the fastening means is deformed to thus tightly hold the button head to the goods.

In most instances, tack buttons are provided with an anchor or die and often an anvil so that the tack, when driven into the button head, will have its prong bent and deformed to thus assure that the button head is securely and irremovably fastened.

One of the objects of the present invention is to provide a solid metal button, preferably a diecasting, in the hub of which is a straight bore or opening and into which is to be driven, during the attaching operation, a novel form of tack, which is of a slightly greater diameter than the bore into which it is to be driven.

The metal of the button head is preferably an alloy, as will be shortly mentioned, and is inherently of such resiliency that when the prong of the specially formed tack is driven into the bore, the bore will slightly expand to receive and compress or grip the prong of the fastener. have found that a button and fastener as abovedescribed have a greater holding power than the ordinary form of tack, which heretofore had to be deformed in the attaching operation.

Still another object of the invention is to pro- K vide a die-cast button. preferably a zinc alloy,

the hub of which is provided with a substantially straight bore, into which is to be driven a tack whose shank is slightly fluted to provide a relatively small twisting action during the attaching operation and whose shank is further provided with a japan or other coating, which acts as an adhesive and is possibly driven into the microscopic tracks between the crystals and adds greatly to the strength of the attachment.

It is to be understood that when we use the words substantially straight bore, we have found it preferable to use a slight draft on the pin around which the walls of the hub are cast to permit the ready withdrawal of the casting as above-mentioned, is for the purpose of permitting the die casting to be readily withdrawn from the pin forming the bore.

Still another object of the invention is to provide a die-cast metal button having a straight bore in its hub, in which is to be driven a tack prong having flutes, the prong also being coated or japanned, thus providing a button and fastening means that is stronger than the ordinary form of tack button and, at the same time, does away with the necessity of anvils, dies, anchors, and other parts inherent to the ordinary form of tack button.

With these and other objects in View, the invention consists in certain new and novel features and combination of parts, as will be hereinafter more fully explained and pointed out in the claims.

Referring now to the drawing showing a preferred embodiment,

Fig. l is an enlarged side elevation of the new tack fastener;

Fig. 2 is a bottom plan view thereof;

Fig. 3 is an enlarged top plan View of the button head;

Fig. 4 is a sectional View thereof;

Fig. 5 is a bottom plan view thereof;

Fig. 6 is a sectional view of a button head showing a cap over the button head;

Fig. '7 is a sectional view showing the button attached to its cloth;

Fig. 8 is a. microscopic'enlargement of the tack taken on the line 38 of Fig. 1.

At the outset, it might be mentioned that the button head, about to be described, might be made of other metal than the zinc alloy hereinafter mentioned, such as soft steel, which would also require that the fastener be pack-hardened and drawn to the right temper, but as far as we have been able to determine, the following zinc alloy is the most satisfactory, as it is readily diecast in a permanent mold and the walls about the hub of the bore will expand slightly when the fastener is driven into the bore and will then tightly grip the prong of the fastener to hold the button in its attached position.

The preferable alloy is as follows:

Per cent Aluminum 4.1 Copper 1. Magnesium .03 Iron (maximum) .075 Lead (maximum) .003 Cadmium (maximum) .003 Tin (maximum) .001 Zinc Remainder The mechanical properties of this alloy are as follows:

Lbs. per sq. in.

.Charpy impact strength-l7 ft. lbs. on

It Will be understood that the alloy per se forms no part of the present invention but its adaptability is of importance in the present invention.

It will also be appreciated that although the metal has ductile properties, as it is cast under pressure, it is the resiliency or elasticity of the metal that permits the bore to expand as the prong is driven within the bore and then tends to retract or spring back to its normal size to thus tightly grip the prong or fastener throughout its length. Also, the fluted shank tends to cut a slight groove in the metal to thus further add to the strength of the fastening.

It will further be understood that lead and tin and other similar metals would probably be too soft and would not have the resiliency desired. On the other hand, soft steel may be used, but in this instance, the tack will have to be hardened and tempered.

Referring now for the moment to Figs. 3 to 5, inclusive, there is shown a button head, which is die-cast and preferably made from a zinc alloy heretofore-mentioned, the button head comprising the body or head proper I with the integrally formed hub 2. Insignia 3 may be cast in the top surface of the button head to designate the brand or trade-mark or a fanciful design may likewise be impressed in the head when the button is cast.

As shown in Fig. 6, the button head is the same, with the exception that there is a metal cap 4 crimped about the head or body portion, and in this instance, the insignia or design 5, of course, will be pressed in the metal cap 4.

Centrally of the hub, there is formed the bore 6, which extends to a tapered point, as at 1, as it is the bore that'receives the tack or fastener, shortly to be described.

It Will be seen that the diameter of the hub with relation tothe diameter of the bore is not great, as these walls are to expand slightly, about a thousandth or two-thousandths of an inch, when the fastener is driven into the bore of the hub.

Referring now to the fastener, which can be used in this straight bore, as above-outlined, there may be seen in Figs. 1, 2, and 8 the tack 8 with the prong 9, which tack is provided with a head I0, over which is placed a shell II for neatness of appearance. The diameter of the prong 9 is slightly larger than the diameter of the bore to provide a tight driving fit. The prong is pointed at its end, as at l2, so that when the same pierces'the cloth l3 (Fig. 7) it will tend to separate the threads rather than out or mutilate them so that in case the operator in the attaching operation wishes to remove the tack, the cloth with the button and tack may be placed in a special machine to retract the tack. Spreading of the threads rather than the mutilating of the same willnot leave an ugly hole where the attachment took place.

It will also be noted that there are minute flutes l4 arranged about the periphery of the tack prong, so that when the tack is driven by a plunger (not shown) through the goods and into the bore of the button head, there will be a slight turning of the tack with relation to the button head.

As is well known, tack buttons are attached by placing the button heads in one hopper of an attaching machine, while the tacks are placed in another hopper. The button head is fed to the attaching station and then driven down onto the tack, where the latter pierces the cloth and is forced up into the button head.

We have found that it greatly assists in the holding power of the tack to japan the same, and in Fig. 8, which is a microscopic enlargement taken on the line 8-8 of Fig. 1, there is shown the coating or japan l5, which, in reality, provides a skin-like layer over the flutes I4 on the prong 9. Other materials than japan might be used, but we have found that japan is of such a thickness and consistency that it acts as an excellent adhesive to more tightly hold the parts together.

We have also found in actual practice that the fastener and button head shown will withstand a tension or pulling force of over two hundred pounds, which is far greater than that necessary in an attachment of this kind.

It will be understood that the flutes will cut a slight groove in the bore and the lacquer or japan acts as an adhesive between the Walls of the bore and the prong of the fastener.

We have found by repeated tests that the japan or coating materially increases the holding power of the fastener and it might be said that the japan or coating increases the static friction between the two parts. It will also be understood that the walls about the bdre of the hub are relatively thin and are slightly spread when the tack is driven into the here. The metal walls tend to assume their normal position, thus tightly gripping the prong of the tack or fastener throughout its length.

We have further found that a fastener of this construction has a greater holding power than the ordinary form of tack button where the tack is driven up into a die and the prong deformed.

It will be seen that a button formed in the manner above-described consists of but a single piece, thus doing away with ordinary dies, anchors, and .anvils, besides the time and cost which would be necessary to assemble the various parts, where the button is made up of more than one piece.

It will be understood that the prong of the tack may also be slightly tapered a few thousan-dths, say two or three thousandths, smaller at the end than near the head. As heretofore mentioned, the tack may be hardened and tempered and preferably coated with an adhesive, such as japan or other lacquer, which adds greatly to its holding power.

From the foregoing, it will be seen that we have devised a button and fastener that are relatively inexpensive to manufacture. The bore may be accurately cast in the button head and the fastener may be readily driven into the bore in a conventional form of button-attaching machine The holding power of the attachment is even greater than the conventional form of tack button where additional means are usually provided to deform the tack within the button head.

Many slight changes are possible in the construction hereinbefore set forth without departing from the spirit of the invention.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A solid ductile zinc alloy button having a hub provided with a straight bore to receive a fastener, a fastener having a prong of slightly larger diameter than the bore to provide a driving fit with said bore, and the fastener having a relatively hard skin-like coating to act as an adhesive between the walls of the bore and the prong of the fastener.

2. A die-cast solid metal button having a hub provided with a straight bore to receive the prong of a tack fastener, a tack having a fluted prong and said prong provided with a hard skinlike coating suitable for a metal-to-metal fastening, the prong of the tack being of a harder metal than the die-cast button and having a diameter to provide a driving fit within the bore, and the walls of the hub tightly clenching the prong of the fastener after the same has been attached.

3. A solid button head having a hub provided with a straight bore terminating short of the head of the button to receive the prong of a fastener whose diameter is greater than that of a prong of harder metal than the material of the button head and of slightly larger diameter than the bore of the hub to provide a driving fit, the prong of the fastener being thinly coated, the walls about the bore in the hub expanding slightly during the attaching operation to thus tightly grip the prong of the tack, and the coating filling the interstices between the bore and the prong of the tack.

4. A die-cast button the hub of which is provided with a bore to receive and grip a fastening member, a fluted fastener of harder metal than the button head, and a coating of hard material on the prong between the flutes to thereby cause the fastener to more tightly grip the metal walls about the bore when the button is attached.

5. A zinc alloy die-cast button having a bore to receive and hold a fastener having a diameter slightly larger than that of the bore and a fastener of harder material than the button and having a diameter slightly greater than the bore to provide a driving fit, and said fastener coated with a hard film to form an adhesive between the walls of the bore and the fastener.

6. A solid button the hub of which is provided with a bore to receive and frictionally grip a fastener, a metal fastener having a tapered point circular in cross section throughout its length and provided with flutes, an enlarged head on said fastener, and a skin-like hard coating about said fastener to form a filler between the walls of the bore and the fastener.

'7. A solid metal button head the hub of which has a relatively small bore to receive and grip a fastener, a fluted fastener provided with a point adapted to separate the threads of the cloth to which the button is to be attached, the flutes being relatively minute in depth and the fluted fastener having a hard adhesive thereon, and the metal of the fastener being harder than the metal of the button head.

8. The combination of a solid button and a solid tack fastener, the fastener being provided with flutes adapted to partly revolve the fastener when entering the button head, the fastener being japanned, the hub of the button head provided with a bore to receive the fastener, and the japan forming an adhesive between the fastener and the walls of the bore.

9. A die-cast solid metal button having a hubprovi-ded with a straight bore to receive and grip a fastener, a tack having a fluted prong, said prong provided with a relatively hard skin-like coating, the prong of the tack being of a harder metal than the die-cast button and having a diameter to provide a driving fit within the bore, the walls of the hub tightly clenching the prong of the fastener after the same has been attached, and the adhesive coating assisting in the holding power between the tack and the walls of the bore of the button head.

10. A button head having an integral hub, said hub provided with a bore to receive and grip the prong of a fastener, a fastener having a prong the diameter of which is slightly greater than the diameter of the bore of the hub, said pron-g being sharpened and provided with flutes, and the prong having a thin coat of lacquer to act as an adhesive when said prong is driven within the bore of the button head.

FORREST Gr. PURINTON. WM. A. ZWIEBEL. HAROLD N. VERZIER. 

